Material clamps



April 10, 1962 A. SCHWARZBERGER MATERIAL CLAMPS Filed March 23, 1960 4 m mu F mm wwy m w m w M g x 0 M ATTORNEYS.

United States Patent Ofiiice Patented Apr. 10, 1962 3,028,649 MATERIAL CLAMPS Arthur Schwarzberger, A.B.M. Mfg. Co., 1306 S. Pulaski Road, Chicago 23, Ill. Filed Mar. 23, 1960, Ser. No. 16,977 Claims. (Cl. 24-250) My invention relates to clamps for textile materials as treated in quilting machines and the like, and more par ticularly to clamps adapted to be carried by a frame in which the textile material is laid.

One object of the invention is to provide a clamp which is placeable along the sides and ends of the frame in which the textile material is laid, in order that such material may be gripped along the edges prior to stretching for the quilting operation.

A further object is to provide a clamp which is of unitary construction, and adapted to be operated manually.

Another object is to provide a clamp whose mechanism is designed for locking the clamp after it has obtained a grip on the textile material.

An additional object is to include a yielding factor in the novel clamp which will maintain the same in a locked position despite shocks or jars which the clamp or framework supporting it may receive.

An important object is to design a clamp of the above character which is self-contained and without projections in the region of its approach and application.

A better understanding of the invention may be had by reference to the accompanying drawing, in which FIG. 1 is a top plan view of a portion of a clampsupporting frame, showing illustrations of the improved clamp on the left-hand side;

FIG. 2 is an enlarged section on the line 22 of FIG. 1 and showing the clamp in the closed position;

FIG. 3 is a view similar to FIG. 2, showing the clamp in the open position;

FIG. 4 is a section on the line 44 of FIG. 2; and

FIG. 5 is a section on the line 55 of FIG. 4 taken in the top region of the clamp.

Referring specifically to the drawing, denotes an angle bar forming part of the frame to which the novel clamp is applied. The base of the clamp is shown at 12, the lower jaw at 13, a top companion to the base at 1342, and an extension of the top to form an upper jaw at 14. It is seen from FIGS. 1 and 4 that the clamps are fan-shaped, in order that they may gain maximum width when engaging a sheet or assembly of textile material as indicated in FIG. 1. The clamp jaws are also perforated in order to lessen their weight.

FIG. 2 shows that the clamp seats in the angle of the frame bar 10, and that the clamp has a post 17 rising in the rear to receive a bolt 18 directed from the angle bar it in order to secure the clamp to the same.

FIG. 4 shows that the base 12 of the clamp has dual webs 12a rising in the same to form bearings for a crossshaft 19. The latter receive collars 20 on the outer sides of the webs 12a in order to lock the shaft against endwise motion. One end of the shaft receives a handle 21; and the latter may be located at a distant point, as shown in the bottom part of FIG. 1.

The shaft 19 receives a disc 25 between the webs 12a, the shaft having a keyway 19a adapted to receive a pin 25a from the disc 25 in order to fix the same on the shaft; and the disc has a thickened portion 25b extending from both sides.

The top 13a of the clamp has a pendent web 14a in the center to which are pivoted the upper ends of a pair of links 27 as shown at 28. The links 27 are curved in rearward direction, as indicated at 27a; and their lower 2 ends apply to the sides of the thickened portion 25b and are pivotally connected thereto as indicated at 27b.

The top 13a of the clamp is divided at the rear with arms 14]) which extend along opposite sides of the post 17. The latter has vertical slots 17a in such sides; and a cross-pin 30 extends between the arms 14b in the upper ends of the slots 17a. The post has a cavity 17b from the top as seen in FIG. 5; and a compression spring 32 is lodged between the pin 30 and the bottom of the cavity.

When the clamp is open, the handle 21 thereof is swung back as shown in FIG. 3. The clamp may now receive the textile material or assembly 15 in the position indicated by dotted lines in FIG. 1. In order to clamp such material, the handle 21 is swung toward the right as seen in FIG. 3, and toward the lowered position seen in FIG. 2. During this action, the upper jaw 14 of the clamp descends into engagement with the textile material, but the action of the clamp is not completed until the handle 21 has reached the horizontal position shown in FIG. 2. As the handle approaches this position, the disc 25 which has drawn the upper jaw 14 down and the links 27 to straddle the disc-draws on the links with a wrapping action to bring their lower pivotal connections 27b past dead center. This action causes the arms 14b of the top 13a to bear down on the spring 32, so that the spring 32 serves to hold the links against retracting motion, thus keeping the clamp lockedagainst opening from jolts or jars in the operation of the quilting machine or in the handling of the textile material.

It will now be apparent that the novel clamp is constructed in a manner to open wide, as seen in FIG. 3, in order that the textile material may be inserted therein with facility. At the same time, the mechanism of the clamp is entirely within its confines, so that outside objects may not interfere with it. Further, the handle of the clamp is apart from the clamp and may even be located at a distant point, as seen in the lower part of FIG. 1, so that nothing extends from the clamp to cause injury or annoyance when it is approached or operated.

Further, the mechanism of the clamp operates with an advantageous leverage obtained by the disc 25 and the upper jaw 14 through the agency of the links 27. Further, these close with a lateral movement augmented by their curvature to bring their bottom pivot past dead center during the final movement of the handle 21, the gripping point oft he clamp then forming the pivot for the pull on the upper jaw to compress the spring 32. A clamp is thus had which is compact, efllcient and simple.

I claim:

1. A clamp having a base, a support rising from one end thereof, a top companion to the base and connecting at one end with a pivot to said support to extend in poised position when the clamp is open, co-acting jaws formed at the other ends of said top and base, and means for closing the top jaw in relation to the base jaw, such means comprising a cross-shaft between the top and base and journaled in the latter, a rotary member carried by the cross-shaft between the top and base, and link means between the top and said rotary member, the rotation of the shaft effective to draw on said link means and close the top jaw as stated.

2. The structure of claim 1, and said link means curving in the direction of the support toward the lower end, whereby to give the latter a lead to pass dead center when the top jaw closes.

3. The structure of claim 1, said link means curving in the direction of the support toward the lower end, whereby to give the latter a lead to pass dead center when the top jaw closes, and a spring carried by the support and yielding to down-pressure by said pivot from the pull of the link means on the movable jaw to lock the link means against receding from past-center position.

4. The structure of claim 1, said link means curving in the direction of the support toward the lower end, whereby to give the latter a lead to pass dead center when the top jaw closes, said support being a hollow post with vertical slots in its sides, the first-named end of said top comprising arms which straddle the slotted sides of the post, the pivot comprising a cross-pin connecting the arms by way of the slots, and a vertical compression spring seating in the post and supporting said cross-pin, such spring yielding to down-pressure by the rear portion of the top jaw from the pull of the link means on such 4 jaw to lock the same against receding from the pastcenter position.

5. The structure of claim 1, and a handle carried by the cross-shaft for rotating the same, such handle being spaced from one side of said top and base.

References Cited in the file of this patent UNITED STATES PATENTS 1,051,560 Cowles Jan. 28, 1913 1,657,342 Ares et al Jan. 24, 1928 2,377,953 Matton June 12, 1945 

